/*
 *  Copyright (C) 2011 Sherlock Downloader
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.sherlock.plugins.loaders;

import java.net.URLClassLoader;
import java.util.Properties;

import org.sherlock.commons.plugins.engines.AbstractEngine;
import org.sherlock.plugins.exceptions.PluginException;

/**
 * 
 * @author Sherlock Downloader
 */
public class EngineLoader {

	private static final String MAIN_CLASS = "sherlock.plugins.engines.Engine";
	private Properties properties;
	private AbstractEngine engine;

	public AbstractEngine load(URLClassLoader loader, Properties properties)
			throws PluginException {
		this.properties = properties;

		try {
			engine = (AbstractEngine) Class.forName(MAIN_CLASS, true, loader)
					.newInstance();
			readMetadata();
		} catch (ClassNotFoundException ex) {
			throw new PluginException("Missing main class " + MAIN_CLASS);
		} catch (Exception ex) {
			ex.printStackTrace();
			throw new PluginException("Invalid plugin");
		}

		return engine;
	}

	private void readMetadata() throws PluginException {
		String supportsVideo = properties.getProperty("videoSupport");
		if (supportsVideo == null) {
			throw new PluginException("Missing 'videoSupport' property");
		}
		engine.setVideoSupport(supportsVideo.compareTo("yes") == 0);
	}
}
